1. Field
Example embodiments relate to display devices, and more particularly, to reflective display devices using ambient light as a light source.
2. Description of the Related Art
Since reflective display devices may have excellent power consumption characteristics because they do not include a backlight unit (BLU) and a polarization film, unlike transmissive liquid crystal display devices, and may make up for the disadvantages of transmissive display devices because the reflective display devices prevent legibility from being reduced in bright environments. Reflective display devices are used in a variety of products, such as of e-books with e-paper display.
Since reflective display devices use ambient light, reflectance is a relatively important factor. In order to adjust/coincide the reflectance of reflective display devices to the reflectance of paper, newspaper, or the like, which may be a natural reflective display device, many monochrome display devices, most of which use only black and white colors, have been developed. However, consumers are appealed to color display rather than monochrome display and thus some reflective display devices using colors have been suggested. However, color reflective display devices having a satisfactory reflectance have not been developed yet.
Once a reflectance is reduced, brightness, luminosity, or the like is reduced. Although color reproduction is increased by using primary colors, for example, red, green, and blue, having high purity, chroma is reduced due to human visual characteristics, thereby making it difficult for a display device to achieve a desired degree of color accuracy. For example, if even light having high purity, such as light in a short wavelength, is darker than ambient light, colors look dull and muddy.
Accordingly, in order to reproduce colors more effectively, the purity of primary colors needs to be increased and a reflectance needs to be increased for a higher brightness.